The production of thermoset polymers by the ring-opening or methathesis polymerization of cyclic olefins is well known in the art. Numerous patents and literature references, both U.S. and foreign, relate to the ring-opening polymerization of dicyclopentadiene in the presence of a variety of olefin metathesis catalyst systems. One such catalyst system is disclosed by Sjardijn et al, U.S. Pat. No. 4,810,762, wherein substituted phenolic tungsten halides are employed with triorganotin hydrides as a catalyst system. In copending U.S. patent application Ser. No. 278,101, filed Nov. 30, 1988, there is disclosed a catalyst system which comprises a phenol-treated tungsten salt such as the halide or oxyhalide combined with a tin or aluminum compound. Bulk polymerization of dicyclopentadiene in the presence of a catalyst system of this type is illustrated by U.S. Pat. No. 4,729,976.
The ring-opening polymerization of dicyclopentadiene and other cyclic unsaturated compounds finds particular application in reaction injection molding (RIM) processes where monomer solutions of the catalyst components are mixed and injected into a mold where polymerization takes place to form a solid, infusible polymeric product. However, the polymerization of dicyclopentadiene by such a process suffers from several disadvantages. If the polymerization is not virtually quantitative, there will be unreacted monomer in the thermoset product and the molded article will have a most undesirable odor. This odor greatly limits the applications in which the polymerized product can be used. A second difficulty arises from the relatively low and less than desirable glass transition temperature for the polymerized dicyclopentadiene product. A typical glass transition temperature (Tg) is in the 130.degree. C. to 140.degree. C. range. This glass transition temperature also serves to limit the applications for the polymerization product.
It is also known to copolymerize polycyclic polyolefinic monomers such as cyclopentadiene trimers, tetramers and higher adducts with other cycloolefins to obtain higher glass transition temperatures. In European Patent Application 313,838, there is disclosed a process of producing ring-opened polymerization products of higher glass transition temperature by polymerizing cycloolefin monomers such as norbornene or tetracyclododecene in the presence of from about 5% to about 45% of a resinous cycloolefin formed from cyclopentadiene trimers and higher oligomers which may also contain common olefins such as styrene, propylene, butadiene, vinylcyclohexene and isopentene. The resinous cycloolefins are produced by heating dicyclopentadiene in the optional presence of the more common olefin. The polymer products of the European Patent Application have relatively high glass transition temperatures, at times over 210.degree. C., but are difficult to prepare. Lane et al, U.S. Pat. No. 4,899,005, use as feed for a ring-opening polymerization mixture of polycyclic olefins which may also contain small amounts, i.e., less than 20% of .alpha.-olefins such as 1-hexene, styrene and vinylcyclohexene. Numerous other patent references illustrate ring-opening polymerization processes involving other and frequently more complex cycloolefins. It would be of advantage to provide a process for the ring-opening polymerization of polycyclic olefin compounds which is easy and economical to operate and where the products have relatively high glass transition temperatures and no detectable dicyclopentadiene odor.